Applicants claim, under 35 U.S.C. xc2xa7119, the benefit of priority of the filing date of Feb. 20, 2001 of a German patent application, copy attached, Ser. No. 101 09 909.6, filed on the aforementioned date, the entire contents of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to a securing arrangement for transporting and mounting a measuring system used for the determination of the position of two components, which can be moved relative to each other. The present invention further relates to such a measuring system.
2. Discussion of Related Art
Such a securing arrangement is used to fix the scanning device in a defined position (desired position) on the support body of the measuring system during the transport and mounting of the measuring system.
A securing arrangement for transporting and mounting a measuring system of the type mentioned at the outset is known from DE 199 18 654 A1. There, the measuring system includes a linearly extending measuring graduation, a support body bearing the measuring graduation, a scanning device scanning the measuring graduation, which is guided at a defined distance from the measuring graduation, and a mounting base, which is connected with the scanning device for fastening it on one of the two components which are movable in relation to each other. In particular, the two components, which are movable in relation to each other, can be the carriage and the associated bed of a machine tool. The support body with the measuring graduation on the one hand, and the mounting base with the scanning device on the other hand, are respectively fastened to one of the components of the machine tool. The securing arrangement itself has at least a base body, which can be linearly displaced along a guide track of the support body, and a guide element, which is releasably connected with the base body and interlockingly enters into the guide track of the support body, by which the base body of the securing arrangement can be clamped in place on the support body of the measuring graduation for maintaining the mounting base in a defined desired position on the support body during transport and mounting of the measuring system.
A service element in the form of an adjusting screw is used for introducing the force by which the securing arrangement can be clamped in place on the support body of the measuring graduation. Its screw head is arranged on the surface of the base body facing away from the support body and is intended to be operated in the customary manner by a tool. However, here the problem arises that at the end of the mounting of the measuring system on the machine tool the adjusting screw is often hardly accessible to a tool, for example because projecting edges of the machine tool greatly limit the available space. Access is further limited if the surface of the base body on which the screw head of the adjusting screw is arranged faces downward after the measuring system has been mounted. Thus, the release of the adjusting screw, and therefore the clamped connection between securing arrangements and the support body, which must take place at the termination of the mounting of the measuring system on a machine tool in order to release the scanning unit for a movement in relation to the support body of the measuring graduation, is made more difficult.
In a further securing arrangement of the type mentioned at the outset, known from DE 30 20 003 C2, the screw head of the adjusting screw is accessible to an operating tool from the side. However, the spatial arrangement of the adjusting screw required for this cannot be used in connection with a particularly advantageous embodiment of the clamping mechanism of the securing arrangement such as is known from DE 199 18 654 A1.
An object of the present invention is based on creating a securing arrangement of the type mentioned at the outset, whose clamped connection with the support body of a measuring graduation can be released in a simple manner, even after the measuring arrangement has been mounted on a machine tool.
This object is attained by the creation of a securing arrangement for transporting and mounting a measuring system used for the determination of the position of two components, which can be moved relative to each other. The securing arrangement includes a base body, which is linearly displaced along a displacement direction via a guide track of a support body of a measuring graduation of the measuring system and is fixed in place on the support body by clamping forces in order to maintain a mounting base that fastens a scanning device to one of the two components in a desired position in relation to the support body. A service element is provided on the base body and having an operating section for introducing and/or canceling the clamping forces, wherein the operating section of the service element laterally protrudes past a surface of the base body which faces away from the support body and is laterally bordered by a lateral edge, when the base body is fastened on the support body.
The object is also attained by the creation of a securing arrangement for transporting and mounting a measuring system used for the determination of the position of two components, which can be moved relative to each other. The securing arrangement includes a base body, which is linearly displaced along a guide track of a support body and is fixed in place on the support body by clamping forces in order to maintain said base body in a desired position in relation to the support body. A screw with knurling provided on the base body for introducing the clamping forces, wherein the knurling of the screw laterally protrudes past a surface of the base body, which faces away from the support body and is laterally bordered by a lateral edge, when the base body is fastened on the support body.
It is a further object of the present invention to provide a measuring system for determining the position of two components, which are movable in relation to each other.
This object is attained by a measuring system for determining the position of two components, which can be moved relative to each other, the measuring system including a measuring graduation extending in a measuring direction and a support body for the measuring graduation. A scanning device scans the measuring graduation, which is guided at a defined distance from the measuring graduation, and a mounting base for fastening the scanning device on one of the two components, which are movable with respect to each other. A securing arrangement including a base body, which is linearly displaced along a guide track of the support body and is fixed in place on the support body by clamping forces in order to maintain the mounting base in a desired position in relation to the support body. A service element provided on the base body and having an operating section for introducing and/or canceling the clamping forces, wherein the operating section of the service element laterally protrudes past a surface of the base body which faces away from the support body and is laterally bordered by a lateral edge, when the base body is fastened on the support body.
In accordance with this, the operating section of the service element (for example an adjusting screw) required for introducing the clamping forces at least projects laterally past the side edge of the surface of the base body of the securing arrangement facing away from the support body when the base body has been clamped in place on the support body.
The attainment of the object in accordance with the present invention has the advantage that the operating section intended for operating the service element is accessible in a simple manner when the clamped connection between the base body of the securing arrangement and the support body of the measuring graduation is to be released. The release of the clamped connection by operating the service element is considerably eased by this, in particular if there is only little space available above, or below, (depending on the installed position of the measuring system) the operating element.
In a preferred embodiment of the present invention, the service element for introducing, or canceling, the clamping forces (i.e. for creating the clamped connection between the base body and the support body, or for releasing it) is rotatable. In this case, the axis of rotation of the service element extends essentially perpendicularly to the surface of the base body facing away from the support body.
The service element is preferably provided and designed for manual rotation by tangentially acting operating forces, without the use of a tool. This has the advantage that it is possible to do without the use of a tool when releasing the clamped connection.
In accordance with a variation, the operating section can be constituted by an operating knob provided with a knurl and preferably disk-like. In another variation the operating section is provided as a lever. Regardless of how the operating section is actually embodied, the lever ratios must be selected in such a way that the tangentially acting operating forces generate the greatest possible torque in order to make the manual release of the clamped connection easier. A sufficiently large diameter of the disk-like operating head, or a sufficiently great length, should be selected to this end.
The operation of the service element is made easier if the clamping forces required for producing the clamped connection can be generated, or cancelled, by a pivot movement of the operating section over less than 180xc2x0. Because of this the release of the clamped connection at the end of mounting the measuring system is accelerated.
In a further development of the present invention, the service element has, in addition to the preferably manually operable operating section, an engagement section, which is designed for operating the service element by a tool. Because of this it is possible to use a tool when clamping the securing arrangement to the support body of the measuring graduation. Since the measuring system is here freely accessible, as a rule there are no restrictions regarding the use of a tool when making the clamped connection. During the subsequent release of the clamped connection following mounting of the measuring system on the support body of the measuring graduation, the clamped connection is released, as described above, by the manual operation of the operating section of the service element intended for this.
In accordance with an embodiment of the present invention, the service element has a screw thread, to which a counter-screw thread of the securing arrangement is assigned and whose pitch preferably is of such a size that the clamping forces required for making the clamped connection can be introduced, or cancelled, by a rotary movement of the service element over an angle of less than 180xc2x0. The screw thread can act in a self-cutting manner, so that the corresponding counter-screw thread is only provided when the screw is turned in.
The service element can for example be constituted by a screw or a rotary lock, wherein in the latter case a corresponding coarse screw thread is assigned as the counter-screw thread.
Alternatively to a screw, it is possible to use a snap-in element as the service element, for example for providing a snap connection in the manner of a quarter-turn fastener. Here, the clamping forces, which cause the fixing of the securing arrangement on the support body of the measuring graduation, are created when the snap-in element snaps in.
In general, service elements having at least one wedge element for creating clamping forces are suitable for introducing the clamping forces.
Another preferred further development of the present invention is distinguished in that the securing arrangement includes a guide element, which is releasably connected with the base body and interlockingly enters into the guide track of the support body and can be clamped to the support body.
This embodiment of the securing arrangement has the advantage that it makes possible a very solid, essentially rigid, fixation of the scanning device on the support body via the securing arrangement in that the guide element of the securing arrangement is fastened by appropriately sized clamping forces on the support body. At the same time, following the end of mounting it is possible to remove the securing arrangement very simply from the support body by releasing the connection between the base body and the guide element of the securing arrangement. Then the base body can be easily removed from the support body. The guide element either remains in the associated guide track of the support body, or is removed from it. In the latter case, it is easily possible to provide that the guide element is additionally movably connected with the base body by a flexible strip, for example a flexible plastic strip or a film hinge. This additional connection must permit a sufficient mobility of the guide element in regard to the base body in order to be able to remove the former, for example by tilting, from the guide track of the support body after the clamped connection has been released.
Reference is made with respect to further details of this further development of the present invention to DE 199 18 654 A1. Its technical teaching can be combined to its full extent with the present invention.
In a preferred embodiment, the securing arrangement includes two separate base bodies which, spaced apart from each other in the displacement direction, are arranged on respectively one of the front ends of the mounting base of the scanning device. In this case, each one of the two base bodies can have its own guide element assigned to it. On the other hand, it is possible to rigidly connect the two base bodies via a common guide element. In the first mentioned case it is possible to achieve a rigid arrangement of the two base bodies with respect to each other by an additional hoop connecting both base bodies with each other. In the second case mentioned, a secure support on both sides of the mounting base in its desired position is made possible by only three components. Here, the guide element additionally takes on the function of the securing hoop.
Further characteristics and advantages of the invention will become apparent in the course of the following description of an exemplary embodiment, making reference to the drawings.